1. Field
The present disclosure relates to an internal combustion engine fuel supply system and an internal combustion engine fuel supply method.
2. Description of the Related Art
The technology described in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2004-522039 is an example of a known internal combustion engine fuel supply system of this type. In this fuel supply system, fuel supplied from a fuel tank to a separator device is separated into high octane fuel and low octane fuel by the separator device. The separated low octane fuel is directly supplied to the internal combustion engine from the separator device, rather than being stored in a tank or the like.
However, the separated high octane fuel is stored in a dedicated sub tank, and is supplied to the internal combustion engine from the sub tank when the internal combustion engine is in a state operating under high load. Accordingly, good performance of the internal combustion engine in terms of output, fuel consumption, and the like is maintained due to effectively suppressing knocking, in a state in which the ignition timing is maintained at an advanced side. Moreover, the separator device is operated when the liquid surface level of the high octane fuel in the sub tank has dropped to a specific lower limit value, thereby securing the amount of high octane fuel.